2DDD

Unique behavior of a histidine responsible for an engineered green-to-red photoconversion process

Summary for 2DDD

• Entry DOI: 10.2210/pdb2ddd/pdb
• Related: 2DDC
• Descriptor: photoconvertible fluorescent protein, MAGNESIUM ION, SODIUM ION, ... (4 entities in total)
• Functional Keywords: photoconversion, green state, luminescent protein
• Biological source: Favia favus
• Total number of polymer chains: 2
• Total formula weight: 51505.16

Authors

Shimizu, H.,Tsutsui, H.,Nukina, N.,Miyawaki, A. (deposition date: 2006-01-27, release date: 2006-03-07, Last modification date: 2024-10-30)

Primary citation

Tsutsui, H.,Shimizu, H.,Mizuno, H.,Nukina, N.,Furuta, T.,Miyawaki, A.
The E1 mechanism in photo-induced beta-elimination reactions for green-to-red conversion of fluorescent proteins
Chem.Biol., 16:1140-1147, 2009

PubMed Abstract: KikGR is a fluorescent protein engineered to display green-to-red photoconvertibility that is induced by irradiation with ultraviolet or violet light. Similar to Kaede and EosFP, two naturally occurring photoconvertible proteins, KikGR contains a His(62)-Tyr(63)-Gly(64) tripeptide sequence, which forms a green chromophore that can be photoconverted to a red one via formal beta-elimination and subsequent extension of a pi-conjugated system. Using a crystallizable variant of KikGR, we determined the structures of both the green and red state at 1.55 A resolution. The double bond between His(62)-C(alpha) and His(62)-C(beta) in the red chromophore is in a cis configuration, indicating that rotation along the His(62) C(alpha)-C(beta) bond occurs following cleavage of the His(62) N(alpha)-C(alpha) bond. This structural rearrangement provides evidence that the beta-elimination reaction governing the green-to-red photoconversion of KikGR follows an E1 (elimination, unimolecular) mechanism.

PubMed: 19942137
DOI: 10.1016/j.chembiol.2009.10.010

Experimental method

X-RAY DIFFRACTION (1.55 Å)